My back up plan is to solder the gold plated tungsten ribbon.  I also gave a goldSmith with a YAG laser some wrap samples to try.  But I have the spot welder now so I might as well see what it can do.  At worst, I just burn up a couple of wood pencils and learn something.  But boy, 6,200 F is a bitch.

I spent the weekend looking at the physics of the welder and looking at Sunstone Welding videos on tungsten microwelding.  I am greatly encouraged.

Since my welder utilizes capacitor discharge, it is obviously DC.  The micro switch under the paddle initializes the charging cycle (the capacitor has a discharge resistor across the poles, so the charge will dissipate in a few seconds if not used).

It appears possible to weld tungsten wires together under an argon bath.  However, I think that an easier process looks like nickel brazing.  I think that I can place a thin ribbon of nickel along the stick on the side facing the hair, put a dab of brazing paste over it, and wrap the tungsten wire over the ribbon.  A shot or two of the spot welder should braze the ribbon to the tungsten without heating the wire enough to cause embrittlement.  I will still use argon to avoid color changing oxidation (which might be over kill due to paste).  

Hi Chicken.  

Straight argon.  They were using two types of systems.

The first was a capacitor discharge with various tip adapters.  They used a hand held 2” diameter copper disc for welding tungsten screen (neat) and a concentric circle with inner and outer copper electrodes with the argon flowing between them (even neater).  It looked like they used a self darkening welding face shield without the hood for viewer protection.  Do not know voltage or amps but very small spark.  Nothing like carbon rod welding, for sure.  No color change of surrounding metal to indicate high level of heat.

They were using nickel tubes to braze tungsten Rods to each other.  Did not seem to use any flux in process, but likely argon.  

For some applications of capacitor discharge, they used a tungsten rod for one electrode and a copper rod for the other.  They only used copper when discharge welding tungsten.

The other technique was using a hand held tig, but the tungsten tip was on a solenoid actuator so when the tip touched the object, the solenoid recoiled it to initiate the spark while keeping the tungsten tip from welding itself to the metal.  That is out of my price range.

I am going to place a call to them tomorrow.

Just got done talking with Sunstone.  

They said there should not be a problem welding the tungsten wire to itself with a capacitor discharge welder, but they need to dial in parameters to prevent imbrittlement since bow will be in daily use for a number of years.  Sending me sample request form (tungsten wrap on pencil).  Liked placing nickel ribbon layer under tungsten (sending a sample of that as well).  Said stainless steel ribbon would also work.  I asked about putting a dab of brazing paste between nickel and tungsten.  He said not to, since metals are welded and not brazed.

I was wrong on what I thought was a tig set up with the retracting solenoid.  He said that it was a capacitor discharge system as well.  

He said that what I want to do is on the upper end of their capabilities.  They frequent deal in micro amps.  The flash is so small that a conventional auto darkening welding eye shield generally will not trigger, so they signal it through a blue tooth connection with the welding machine.

Hi Gordon and others.  Solder is used to secure the ends of most silver wire wraps.  My new German pernambuco bow uses 0.2 mm diameter silver wire (thinner than the usual), and obviously used a string loop to tuck the ends under the wrap.  Looks nice but I have seen several used ones with loose wrapping.

I so want the copper roller used to weld wire mesh.  I timed out the spark interval as it rolled, and I could perfectly mimic it with the dial a welder.  I could do that all day (if only I could find a client).

Well Chicken, certainly gifts but no free samples.  Been down that road to disappointment.  

Made up a couple of tungsten wrapped pencils with a nickel ribbon underlayer (see photo).  Encouraged that ribbon was so thin that could not see outline under wrap.  

Interesting thread on Cocker bamboo bows on another forum.  Member stated that he had such a bow and it performed the best that he ever played.  Traded it for an inferior bow that had a more conventional appearance.  What more can be said.